Electrical switch



Sepa 25j, 1934.

W. S. MAYER ELECTRICAL SWITCH I Filed June 18. 1932 I N VEN TOR.

Patented Sept. 25, 1934 mural) STATES,

PATENT -OFFICE My invention relates to electrical switches, moreespecially to those of the automatic type, for use in connection witheither direct or alternating current circuits.

An object of my invention is to provide an electrical switch which shallbe simple in construction, capable of preventing the operator from fullyclosing the switch, or holding it closed during the existence orcontinuance of predetermined electrical conditions in a circuit, and toaccomplish these results in a much improved and sim- -pler manner thandisclosed in my previous Patent No. 819,360 dated May 1, 1906.

Another object of my invention isto provide a U-shaped housing for thebridging element or' contact member, and actuating mechanism, that canbe arranged to accommodate a lsolenoid forsmall current capacities, andarranged to omit the solenoid for large current capacities.

My invention also consists of certain features of construction, as willbe fully described, and

- pointed out in ldetail in the description, the drawl the arrows 2-2 inFig. 1 with the cover componentof the casing removed and the solenoid 29partl,7 shown. l

Fig. 3 is a. sectional view of the device taken as indicated by thearrows 3-3 of Fig. 1.rk

Fig. 4 is a sectional view taken as indicated by the arrows 4-4 of Fig.1.

Fig. .5 is a perspective view of the carriage of the bridging element orcontact member.

Fig. 6 is a perspective viewof the amature.

Fig. '7 is a perspective vie'w of the bi-metallic element or thermicelement which is relied upon to trip the circuit breaker upon smallabnormal circuit conditions.

Fig. 8 is a perspective view of the disengageable toggle link.v

Fig. 9 is afragmentary view taken as indicated by the arrows 9 9 of Fig.3, and shows the bridging element pulled to the extreme oiI position'bythe disengagement of the toggle link, with the actuator 44 manuallyheld.

With more specific reference to the drawing a vertical-elongatelongitudinally split, b0x11ke casing 15 of moulded dielectriccomposition encloses the working mechanism hereinafter described ingreater detail. As shown a base component 16 and a cover component 17meet in a rabbeted juncture' 18 Ywhereby the two components are held inperfect alignment and registry.` The cover component 1'? has openingsfor the passage o! arc flashes, and is removably secured by screws 19which pass through the openings in its side walls to engage the threadedmetallic bushings 20, embedded in the base component 16, see Fig. 2 andFig. 4. Counterbored holes are provided in the base component for panelmountings or the like.

Secured within the base component are terminals 21 and 22 formed ofconducting metal, as for instance, brass, and the said terminals havebinding screws 26, 26a for line wire connections, which line wireconnections pass through holes in the end walls of the base component.The terminals are secured to the base component by screw bolts 23-23.Secured within the base component are/contacts of brass, or the like, 24and 25 which are of conilgured construction, for the installation ofU-sh'aped blow out magnets, if found desirable. To the terminal 21 andthe contact 24 are electrically c nnected atl 27 and 28 the ends of aninsulated c nducting coil or solenoid 29. 'Ihe solenoid envelops an ironcore 36 having insulating discs 37-3'7 acting as bobbin heads. The core36 is fastened to a removable cross yoke 38 which yoke is attached byscrews 38a and 38h to depressed lugs 39a and 40a on bracket-like guides39 and 40, which guides are made of steel and form a magnetic housing.'Ihe guides 39, 40 guide the bridging element 41 in a translatorydirection in the Islots 42 and 43, and, also, provide a bearing supportfor the actuator lever 44.

To the terminal 22 and contact 25 are electrically connected at 30 and31,the legs of a bi- 4metallic element 32. The bi-metallic element,

shown in perspective in Fig. '7, is a slotted element and has legs 32aand 32h which are pierced, as at 34 and 34a, to accommodate rivets 34c,which secure the legs electrically and mechanically to the terminal 22and the contact 25 as previously stated. The legs ofthe bi-metallicelement are joined at 33 thus forming a continuous electrical path, andon the junction 33 is secured the insulating pillar 35.

c The guides 39 and 40 are securedcin spaced relationship within thecentral' chamber of the base component 16 of the casing, by means ofscrews 45 and 46 which pass through the back walls of'the base componentand into the foot ilanges 47 and 48 of the guides. Adjacent the footends of the guides, an iron armature 50, shown in perspective in Fig. 6,is pivoted by a freely through the slot.

brass pin 51 passing through brass. saddles 52, which are secured to thearmature, and also through the guides. The armature is maintainedretracted away from the guides by a spring 53. The armature is slottedas at 54 so as to allow the pillar 35 of the bi-metallic element to playIt will be noted that the guides 39 and 40 reach into thechamber of thecover component 17 and are connected by a steel cross bearing pin 49.-

The bridging element or contact member 41 comprises an open slidemember, generally designated as 54, preferably formed of copper orbrass, see Fig. 5, with spaced parallel side portions 55, 56. The sideedges of the side portions 55, 56 are connected by traverse yokes 57,,58 which latter are pierced as at 59, 60 for rivets whereby theconducting leaf springs 61, 62 for .taking the conducting blocks 63, 64are secured to the yokes. These blocks are pressedagainst the outersurface of the contacts 24, 25 when the switch is in the closed positionas shown. The side portions of the slide member are formed withoutwardly bent lugs 66, 67 for engaging the longitudinally directedslots 42, 43, of the guides 39, 40. Between the side portions 55, 56,three rollers 68, 68, 69 are rotatably mounted about a pin 70 whichpasses through the rollers, the pin is secured to each side portion.Rollers 68, 68 are grooved to accommodate the eye ends of springs 71,71.The roller 69 which acts as a catch member is positioned to engageinternal hooks 73,73 of a latohing link 72. 'I'he link 72, shown inperspective in Fig. 8, consists oftwo similar punchings spaced by aninsulating bushing 74 and-having extending bushings 75,all of which areriveted together by a pin 76.

The actuator lever 44 consists of a moulded dielectric compositionfinger piece 77 which swings within an opening in the front wall of thecover component 17 and the said tlnger piece is so shaped that itsrotation, to and fro motion, is limited by projections on the fingerpiece as shown. Embedded 'in the linger piece is a U- shaped metalliclever member 78. The actuator 44 pivots on the pin 49 and is in spacedrelation by rollers '19, 79 between the guides 39, 40 as shown. Therollers 79, 79, seeFig. 9, are grooved to accommodate the other ends ofthe springs 71, 71. A pin 80 forms a pivotal connection to which isconnected-the U-shaped member 78 and the link 72. The spring 81enveloping the pin 80 engages at one end thereof, the arm of the U-shaped member '78 and the other end of the spring engages the link 72 soas to tend to move the link counterclockwise about the pin 81. As willbe noted the link 72 also envelops the roller 69. When the hooks 7 3 areengaged with the roller 69, the U-shaped member 78 and link 72 form atoggle action to permit moving the bridging element 41 from openposition toward the closed position and when pivot 80 passes over thedead centerrelation 79, 80, 49, the bridging element is held intheclosed position against the action of the springs 71, 71.

When abnormal circuit conditions occur either the bi-metallic elementfunctions and presses the pillar 35 against the bushing 74v to disengageby raising the hooks 73, 73 from the roller 69, or the armature isattracted upwardly to strike the bushings 75, of the link 72 todisengage the hooks 73 from said roller 69. As a consequence thebridging element is rapidly pulled to open position by the springs 71,71. It will be noted by reference to Fig. 9 that whether the `Serial No.614,499.

finger piece 77 is manually held or not, the link 72 is tripped asaforesaid. Due to the fact that the spring 81 presses the link 72 in acounterclockwise direction, it will be evident that the actuator whennot manually held will be rotated around clockwise by reason of thepressure of the link throat 82 against the roller 69. It will also beevident that the actuator `may be manually operated to break the toggleaction of 72 and 76 to allow the bridging element to be pulled by 85 thesprings 71, 71 from the closed to the open position. In order to obtaina quick manual breaking action, the actuator may be readily. modified asshown in Fig. 14 of my application Referring to Figs. 1, 2, and 4, itwill be noted that in the closed position of the bridging element, thecircuit through the device is from binding screw 26 through theterminal- 21, the solenoid 29, the contact 24, the bridging element 41,the contact 25, the bi-metallic element 32, the terminal 22 to thebinding screw 26a.

The removable solenoid, comprising elements designated as 29,36, 3'7,38, 38a, and 38h, is incorporated for small normal current capacities tobring up the ampere turns necessary to attract the armature oncorrespondingly abnormal circuit conditions. For larger normal currentcapacities, the solenoid is not necessary as there is suiilcientmagnetism induced in the guides 39, 40 and pin 49, by the bridgingelement, to attract the armature on correspondingly abnormal circuitconditions. When the solenoid is omitted, the contact 24 and terminal 21are linked together between 21 and 28. No change is made with thebi-metallic element. n

Although my invention has been described in considerable detail, suchdescription is intended as illustrative rather than limiting, since theinvention may be variously embodied. My invention, therefore, is not tobe restricted except so far as it is made necessary by the prior art andby the spirit of the appended claims.

Having thus described my invention, I claim:

' 1. In an electric switch, a movable bridging 120 element, a catchmember on said bridging element, a toggle for operating said bridgingelement, said toggle consisting of an actuator and an apertured link,said link having an opening therein whereby the opening cooperates toenvelop and engage the catch member on the bridging element, and saidlink being restricted in movement by the relationship of the opening andthe catch member when the bridging member is in' open circuit position.

2. An electric switch comprising a plurality of contacts adapted to beconnected to an outside circuit, an apertured bridging element for saidcontacts normally biased to open circuit position but movable to closedcircuit position, a latching link at one end adapted to pass through theaperture of said bridging element and adapted to engage a catch securedto said bridging element, the opposite end of said link pivoted to anactuator, said link and actuator forming a toggle which is overset andis adapted to hold the bridging element in normally closed circuitposition, and means operable by abnormal circuit conditions fordisengagin'g the link from the catch member.

3. as en article of manufacture an electric switch comprising anelectromagnet; contacts adjacent to the opposite ends of said magnet; arectilinearly reciprocable apertured bridging element guided by 'saidmagnet and bridging said 150 'said contacts; a latch passing through theaperture of said bridging element adapted to engage the catch secured tothe bridging element, means for operating said latch to move thebridging element toward said contacts, and means opefrable by abnormalcircuit conditions for disengaging the latch from the catch therebypermitting movement of said bridging element away from said contacts.

4. In an electric switch, spaced contacts, switching mechanism includinga movable bridging element for making and breaking an electricalconnection between said contacts, means adapted to lock said bridgingelement in closed circuit position, means including a spring adapted tomove said bridging element from its closed circuit position, asubstantially U-shaped magnet enveloping the bridging element, anarmature pivoted between the open legs of the magnet to close themagnetic circuit thereof and adapted to release said means to .lock saidbridging element in closed circuit position upon abnormal circuitconditions in the bridging element, and means provided on the said Ushaped magnet todetachably secure a solenoid in series with the circuitthrough the spaced contacts in order to increase the ampere turns foractuating the armature to release the rst said means upon other abnormalcircuit conditions.

5. In an electric switch comprising a plurality of spaced contacts,switching mechanism normally biased away from both of said contacts andincluding a movable bridging element adapted for bridging said contacts,a catch member on the bridging element, means for moving said bridgingelement toward said contacts including an apertured link, saidlink-having an aperture therein defining an internal hook, said -hookbeing adapted to envelop and engage a catch member on the bridgingelement, and said link being overset when the bridging element is in aclosed position, and a current responsive device for disengaging saidlink and releasing said bridging element upon the ow o1' abnormalcurrent.

6. An electric switch comprising a plurality of spaced contacts,switching mechanism normally biased away from said contacts andincluding a movable bridging element adapted for bridging said contacts,a catch member on said bridging element, a toggle for operatingsaid'bridging element, said toggle consisting of an actuator and anapertured latching link, said aperture defining a hook for envelopingand engaging a. catch member on said bridging element, said toggle beingthrown over dead center to normally hold the bridging element inelectrical connection between said contacts, and abnormal circuitresponsive means for disengaging the link thereby permitting movement ofsaid bridging element away from said contacts.

7. An electric switch .as set forthin claim 6 in combination with meansforl automatically returning the lactuator to the full of! position whenthe latching link is disengaged and the actuator is not restrainedmanually.

. WALTER S. MAYER.

